Open-source alternatives to Harvest and Toggl

At a glance

Open-source alternatives to Harvest and Toggl compared
Tool	Licence	Self-hosting difficulty	Who it suits	Strengths
Kimai	AGPL-3.0	Easy to moderate: PHP 8.2 or newer with MySQL or MariaDB, on its own subdomain. Docker image available	Small agencies, consultancies and freelancers who bill by the hour	Unlimited users, timers and timesheets, teams, invoices as PDF or DOCX, Excel and CSV export, API, SAML, LDAP and two-step login

Kimai: AGPL-3.0. Some plugins are sold separately, as one-off purchases. Licence checked 31 October 2026.

If you bill by the hour, time tracking isn't a nice-to-have. It's where your invoices come from. Harvest Teams and Toggl Track Starter both cost $9 per user a month on annual billing, which is $1,080 a year for a team of ten. Toggl Premium, which adds things like timesheet approvals and profitability reports, is $16 a user.

Neither of those is outrageous. But it's a cost that grows with every person you hire, for a job that's basically "record some hours, then turn them into an invoice". That's a job an open-source tool can do well.

There's one tool I'd point you at, because it's frankly the obvious choice.

Kimai

Kimai is a web-based time tracker that's been around for years, and it's kept very active, with regular releases. It's designed for exactly this: teams recording time against customers and projects, then billing for it.

Timers and timesheets, with a time-clock mode if you want staff limited to clocking in and out.
Unlimited users, each with a role, and no per-user charge when you self-host.
Teams, so you can limit who sees which customers and projects.
Customers, projects and activities, which is the usual structure for agency billing.
Invoicing built in, with templates, numbering, and PDF or DOCX output. Harvest does this as well, so it's a fair like-for-like.
Exports to Excel, PDF, CSV and HTML, and you can lock exported records so nobody changes them afterwards.
An API, so it can talk to your other systems.
Single sign-on and security: SAML and LDAP login, with Google Workspace or Azure AD for example, plus two-step login.
Over 30 languages, if your team is spread around.

Running it is about as easy as these things get. It needs PHP 8.2 or newer, MySQL or MariaDB, and either nginx or Apache. It has to sit on its own domain or subdomain, because subfolders aren't supported. The normal install is over SSH with Git and Composer, and there are Docker and Kubernetes options too. It also works on many shared hosts, though it does need command-line access, so plain FTP hosting won't do.

Plugins are how Kimai handles anything specialist. A few are worth knowing about:

Timesheet approval: there's a free plugin for weekly approval.
Working hours, holidays and sickness: 299 euros, one-off. Handy if you want to use it for staff hours as well.
Expenses: 99 euros.
Custom fields: 99 euros.
Microsoft Teams integration: 99 euros.

The prices here are from Kimai's store. For most small teams, you'd want one or two at most. Compare that with paying every month forever, and it's a small cost.

There's a middle way too. If you like the sound of Kimai but don't want to look after a server, Kimai Cloud is hosted in Germany and starts at a few euros per user a month, with Professional adding the working hours, expenses and single sign-on features. That's cheaper than Harvest or Toggl, though it does bring the per-user fee back.

What it costs

Harvest and Toggl

Harvest Teams: £6.82 per user a month, billed annually (converted from $9 at the European Central Bank reference rate on 2 October 2026). Checked 31 October 2026 (source).
Toggl Track Starter: £6.82 per user a month, billed annually (converted from $9 at the European Central Bank reference rate on 2 October 2026). Checked 31 October 2026 (source).
Toggl Track Premium: £12.12 per user a month, billed annually (converted from $16 at the European Central Bank reference rate on 2 October 2026). Checked 31 October 2026 (source).

Self-hosted, run for you

No per-user fees. Adding people doesn't add licence costs.
Setup: a one-off fee to set it up and move your data across.
Hosting and care: a fixed monthly fee covering every app on your server.
I'll quote once I know what you need.

Paid tool prices exclude VAT unless stated.

The UK angle

Timesheets aren't usually the most sensitive data you hold, but they do record what named staff did, and when. If you use them to track working hours or sickness, that's personal data under UK GDPR, and sickness records in particular need more care.

Harvest and Toggl are fine for most small firms, and I wouldn't switch just because of where they're hosted. It's a nice extra that with self-hosted Kimai everything's on your own server, and with Kimai Cloud it's in Germany.

The more practical point is ownership. Timesheets are the evidence behind your invoices, and if a client disputes a bill, you want the records to hand. With Kimai the database is yours, and you can export everything in standard formats whenever you like.

One thing to be careful of: Kimai isn't an accounts package. Your invoices still need to be right for VAT, so check that the template shows what it should. If you're under Making Tax Digital rules, your accounts software is still where the records need to end up.

Honest drawbacks

The phone experience needs checking. Kimai's docs cover using it from your phone's home screen. I couldn't confirm an official native app, whereas Harvest lists Mac and iPhone apps on its pricing page. If your team tracks time on the move, look at this first.
Fewer ready-made integrations. Harvest and Toggl connect to lots of other tools. Toggl's Premium plan has Jira and Asana built in. With Kimai you'll mostly use plugins or the API.
It looks like a business tool. Don't expect the polish of a product with a big paid design team behind it.
Some good bits are paid plugins. Budget for one or two if you need holidays or expenses.
Someone has to run it. Backups particularly matter, because this is your billing data.

Which one?

My pick is Kimai, self-hosted. It covers timesheets, teams and invoices with no per-user fee, and it's light enough to sit on ordinary PHP hosting. The main drawback is that it's a less polished experience than Toggl, particularly on phones, so check that side of things with your team before you switch.

Small agency or consultancy billing by the hour: Kimai, self-hosted.
Want Kimai without running anything: Kimai Cloud.
Lots of mobile users, or heavy use of integrations: stay on Harvest or Toggl.

If you need your time data feeding into your own systems, such as job costing or a client portal, the team at Dev Partners can build that as custom software.